401(k) Contribution Calculator

See what your paycheck contributions and employer match could grow into — everything updates live and nothing leaves your browser.

📖 How it works & FAQ

Annual salary ($)

Your contribution (% of salary)

Current 401(k) balance ($)

Employer match (% of what you put in)

Match limit (up to % of salary)

Years until retirement

Expected annual return (%)

How this 401(k) projection works

The calculator figures your yearly contribution (salary × your contribution %), then adds the employer match: your employer contributes a percentage of what you put in, but only on contributions up to the match limit. For example, a common formula is "50% match up to 6% of salary" — if you contribute 6% or more, the employer adds 3% of your salary. Each year, your balance grows by the expected return and the combined contribution is added, compounding annually until retirement. Everything runs privately in your browser; no numbers are sent anywhere.

Why the employer match is free money

The match card shows exactly how much your employer adds each year — and if your contribution is below the match limit, how much you're leaving on the table. Capturing the full match is an instant, guaranteed return on that slice of your paycheck before any market growth. If you can only do one thing for retirement, contributing at least up to the match limit is usually it.

How to use it

Enter your annual salary and the percentage of it you contribute.
Set your employer's match formula: the match percentage and the salary cap it applies up to (check your benefits page).
Add your current 401(k) balance, years until retirement, and an expected annual return (6-8% is a common long-run assumption).
Read the cards: projected balance, yearly contributions split between you and the employer, and how much of the final number is pure investment growth.

These are simplified estimates only — not financial, tax, or investment advice. Real results depend on market returns, fees, raises, and IRS contribution limits.

FAQ

What return rate should I use?: Many planners use 6-8% for a stock-heavy portfolio before inflation, and 4-5% for a conservative mix. Try a few values to see a realistic range rather than a single number.
Does this account for IRS contribution limits?: No — it applies your percentage directly. The IRS caps employee deferrals each year (around $24,500 in 2026, more with catch-up contributions after age 50), so check current limits if you're a high earner.
Does it include raises or inflation?: It assumes a flat salary and contributions, so real-world results with raises are often higher in dollars — but inflation also reduces future purchasing power. Treat the output as a today's-dollars ballpark.
Is my data stored or sent anywhere?: No. All math happens locally in your browser and nothing is saved or transmitted.